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The constrained groove pressing-cross route process was implemented on a commercially annealed AA5052 alloy at room temperature, with up to two passes (strain of ∼4.64) along the rolling direction and transverse direction. The results showed the formation of an ultrafine-grained structure with an average sub-grain/cell size in the 300–500 nm range. The indentation hardness and tensile strength increased significantly, up to ∼75 and 105%, respectively, and became more homogenous with a uniform and isotropic trend, as compared to the annealed alloy. According to the Hall–Petch and Taylor models used, grain refinement and increasing dislocation density were proposed as the main strengthening mechanisms. Fractographic studies revealed a ductile-fracture behaviour, with a dimpled structure proportional to the UFG structure.

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In contrast with all advantages of composite materials, susceptibility of these materials to impact damage became a major concern recently. The aim of this research is to investigate the dynamic response of laminated composite cylindrical shell subjected to pure impact numerically. For this purpose, the impact of a steel ball on composite cylinder is modeled in Abaqus software as a point load and the amount of radial deflection and contact force of the contact point on cylinder surface is recorded for whole period of contact motion. To validate the obtained results they were compared with the exactly the same model in published data. According to obtained results, both of radial deflection and contact force have a parabolic variation during the impact motion. The maximum radial deflection occurs when the striker has its maximum penetration and bouncing back motion is just about to start.